There is a train that leaves at 20:21 departing from Cambridge. Would you like me to book that for you?
Can you tell me what the train ID is for the train that arrives at 20:21?
attraction-name attraction-type train-day train-departure train-destination train-leaveat
attraction-name attraction-type train-day train-departure train-destination train-leaveat
attraction-name attraction-type train-day train-departure train-destination train-leaveat
attraction-name attraction-type train-day train-departure train-destination train-leaveat